The present invention is directed to painted fastener and washer assemblies. More particularly, the present invention is directed to a fastener and washer assembly which facilitates the application of paint and a method of making a painted assembly.
As the automotive, applicance, and building industries become increasingly corrosion conscious, various ways of preventing fastener corrosion become increasingly important. One way of halting corrosion is to dip or spray coat the assembled fastener and washer to match the color of the exposed panel. Several problems have arisen. First, the washer-fastener interface causes some of the surface area to be difficult to coat. Second, if this difficulty is overcome, when the painted assembly is baked, or dried by other means, the paint in the interface region forms a bond between the two elements of the assembly. Since the washer's primary function is to remain free-spinning thereby preventing marring of the panel beneath, such adhesion is unacceptable.
One solution to this problem is to paint the washers and fasteners before assembly. Unfortunately, this solution creates more problems than it solves. The washers tend to nest and the coverage and adherence problems are more pronounced than with the pre-assembled washers and fasteners due to the larger interface. When the washers are separated after the paint has dried the coating on each is generally marred and both washers must be discarded. Separate inventories of painted fasteners and washers must be maintained for each color, with the possibility of variations in die lots, as well as the concommitant handling problems including the care with which pre-painted elements must be assembled.
The present invention solves these problems. A pair of annular protrusions are formed on the fastener shank between the head and the threads. The washer is then partially assembled with the fastener, the inner peripheral edge of the washer being retained between the two protrusions to hold the washer in spaced relationship with respect to the fastener head. The assembly can now be coated with paint with all the important surfaces being readily accessible for painting. Should the small interface between the inner peripheral edge of the washer and the shank of the fastener be sufficient to cause a paint bond to be formed, movement of the washer to its fully seated position following drying of the paint will break the elements loose and re-establish a free-spinning condition. A method of making this assembly is also disclosed. Other characteristics, features and advantages of the present invention will become apparent after a reading of the following specification.